Bioactive compounds in cash crops can be obtained from horticulture, oil and medicinal crops sources. Conventional extraction methods have disadvantages such as low extraction rate, large solvent consumption, high energy consumption and long production cycle. Ultrasonic-assisted extraction is a novel, green and rapid developing technology, which is suitable for up scaling and improving the extraction efficiency of bioactive compounds. Ultrasound mainly acts by producing cavitation bubbles in biological matrix. It has inclusively been reported for achieving high yields and extraction rates of bioactive compounds. Moreover, it can bring remarkable economic and environmental benefits, and has great potential for development and application. This review summarizes the mechanisms, effects of ultrasonic-assisted extraction, ultrasonic devices, and their application in bioactive compounds extraction from cash crops. The future perspective of ultrasound technology is also discussed, which will help to better understand the complex mechanism of ultrasonic-assisted extraction and further guide its application in cash crops.

In recent years, there has been increasing interest in renewable and sustainable protein resource of plant origin. The reasons for this are summarized as follows: (1) green, low-cost, environmental friendly and sustainable concepts are deeply rooted in people's minds; (2) long-term use of animal protein can lead to high blood pressure, obesity, negative environmental impacts; (3) more and more vegetarians are emerged; (4) many consumers still do not accept food grade insect. Based on this situation, this paper links eco-innovative ultrasound technology to plant-derived sustainable proteins resource, and magnifies the advantages of both at the same time. Ultrasound is a novel, green and rapid developing environmental friendly technology, which is suitable for up scaling and improving the physicochemical properties of protein. This review summarizes the mechanisms, cavitation properties of ultrasonic field, consumption of energy, applications of spectroscopic techniques for evaluating plant-derived proteins conformation changes, effects of ultrasound on the structure and physicochemical properties of plant-derived renewable proteins, and application of ultrasound treatment proteins in food industry. Furthermore, future research to better utilize this green technology is suggested. In this way, it not only conforms to the concept of sustainable, high-efficiency, and environmental protection of the food protein industry, but also clarifies the relationship between protein structure and properties, which are conducive to the application of ultrasound in protein industrialization.